What is the negative square root of 81?
Understand the Problem
The question is asking for the negative square root of the number 81. The square root of 81 is 9, so the negative square root would be -9.
Answer
The negative square root of 81 is $-9$.
Answer for screen readers
The negative square root of 81 is $-9$.
Steps to Solve
- Find the square root of 81
To begin, we need to determine the square root of 81. The square root of a number $x$ is a value $y$ such that $y^2 = x$.
Calculating this gives us:
$$ \sqrt{81} = 9 $$
- Consider the negative square root
Since the problem specifically asks for the negative square root, we simply take the negative of the square root found in the previous step:
$$ -\sqrt{81} = -9 $$
The negative square root of 81 is $-9$.
More Information
The negative square root of a positive number is simply the negative value of its positive square root. In this case, since the square root of 81 is 9, the negative square root is -9.
Tips
A common mistake is to only consider the positive square root and forget about the negative counterpart, especially when specifically asked for the negative square root.
